A variety of multiple link chains are known which generally include individual lengths which are pivotably connected to like links by means of pivot pins in order to permit relative pivotable movement of adjacent links about the axis of the pivot pin. This type of chain is normally arranged in an endless configuration and driven by a sprocket wheel.
Several basic types of such a chain are known. The first type is called a mattop chain and is well known in the trade. This type of chain includes a plurality of modules which are constructed in a multiple link width wherein the plurality of links across a given width of conveyor are pivotably connected to a corresponding plurality of lengths both ahead and behind thereof. A conveyor belt or the like of any width and length may be assembled from the mattop chain links and the conveyor belt is adapted to transfer articles to and from the belt by means of a cooperative transfer comb. However, a limitation to a mattop link conveyor belt is that its construction will only allow for straight line movement and, as desired, transfer of articles from the conveyor to a cooperatively associated transfer comb. The mattop chain link conveyor belt is not adapted to accommodate a curve or bend during the upper run thereof. This type of conveyor belt is described in a number of patents including U.S. Pat. Nos. 4,171,045 and 4,051,949 to Lapeyre.
A second general type of modular conveyor belt is constructed of what are commonly known as table top chain links. These links are typically connected together into an endless belt of only a single link width. A modular conveyor belt constructed of table top chain links is desirable since the links are relatively pivotably movable both vertically and horizontally so that the conveyor belt can accommodate a bend or curve during the upper run of the endless belt. However, although the conveyor belt constructed of table top chain links has the distinct advantage of being able to accommodate a curve or bend during the upper pathway thereof, the transfer of articles therefrom can be accomplished only by side-transfer techniques requiring a parallel and separate conveyor belt onto which articles are directed from the first belt by a guide or the like. A manner in which to effect straight line transfer from a table top chain link conveyor belt has not been known until now. Patents of possible interest relating to table top chain links include U.S. Pat. Nos. 4,436,200; 3,804,232; and 3,262,550.
A variation of the table top chain link is what is known as the low backline pressure roller chain which essentially comprises a table top chain having a plurality of small, closely-spaced rollers on the top surface thereof in order to protect products from damage by significantly reducing backline pressure during accumulation on the conveyor belt. At the same time, the chain provides for positive motion when required. This type of table top chain also is adapted for both vertical and horizontal pivotable movement so as to accommodate a curved pathway, but up to this time only side transfer techniques requiring a separate and parallel conveyor belt have been utilized in order to transfer articles being conveyed thereby. Applicant's invention provides for a new and improved low backline pressure table top chain link which will also accommodate in-line transfer of articles being conveyed thereby onto a cooperatively associated transfer comb and conveyor belt or the like.
Therefore, it can be appreciated that applicant has provided for a new type of table top chain link which allows for the construction of a modular conveyor belt having the heretofore unavailable capability of in-line transfer of articles being conveyed thereby onto another conveyor belt. Both conventional and low backline pressure table top chain links are contemplated to be modified according to applicant's invention.